I have noticed this behavior with IE6. It appears that in IE6, nested tables inherit the justification of the table above it (the old behavior was to assume left justification). Unfortunately, there's no way to "fix" that on the client side. It appears that this is Yet Another item that our Fearless Leader will have to address if he so chooses.
"One word of warning: if you meet a bunch of Perl programmers on the bus or something, don't look them in the eye. They've been known to try to convert the young into Perl monks." - Frank Willison